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Miller MW Church CC Miller RK Edwards MJ 《Birth defects research. Part C, Embryo today : reviews》2007,81(3):135-143
There are a number of seemingly \"usual\" thermal episodes during pregnancy for which it is relatively easy to determine a rudimentary aspect of thermal dose; these episodes include fever, labor, labor plus epidural, and the normally-occurring 0.5 degrees C temperature elevation above maternal core temperature of the fetus during the entirety of the third trimester. Complications can involve, for instance, fever during the third trimester. We consider the thermal doses of five different but \"usual\" or \"normal\" hyperthermic episodes during human pregnancy and compare those doses with the thermal doses involved with both single and cohort exposures of pregnant guinea pigs throughout their gestational period. The end-point studied in the guinea pigs was microencephaly. In nine of the 10 comparisons (human fetal thermal dose vs. guinea pig fetal thermal dose) the human dose is substantially larger than that of the guinea pig thermal dose, which was substantially teratogenic. This situation is essentially the inverse of the type of information contained in the Physician's Desk Reference (PDR) on drugs, in which it is not unusual to discern that at high drug levels there may be teratogenic effects in laboratory animals, but such effects were not observed at \"clinical\" drug levels in animals or subsequent clinical trials. With hyperthermic events, however, it appears that the teratogenically-effective thermal dose levels associated with animal testing are quite low relative to those thermal doses associated with relatively \"normal\" obstetric observations during a pregnancy. 相似文献
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Dose-response relationship between body temperature and birth defects in radiofrequency-irradiated rats 总被引：3，自引：0，他引：3
Five groups of pregnant Sprague-Dawley rats were irradiated for 10-40 min on gestation day 9 in a 27.12-MHz radiofrequency field at a magnetic field strength of 55 A/m and an electric field strength of 300 V/m. The specific absorption rate was 10.8 +/- 0.3 W/kg. Exposures were terminated after the rat's colonic temperature reached 41.0 degrees C, 41.5 degrees C, 42.0 degrees C, 42.5 degrees C, or 43.0 degrees C. A control group was sham irradiated at 0 A/m and 0 V/m on gestation day 9, whereas a second control group was untreated. The incidence of both birth defects and prenatal death was directly related to maternal body temperature once a temperature threshold was exceeded. The temperature threshold for both types of effects was approximately 41.5 degrees C. A few pregnant rats died after exposure to 43.0 degrees C, and higher temperatures were nearly always lethal. 相似文献
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An episode of hyperthermia is not uncommon during pregnancy. The consequences depend on the extent of temperature elevation, its duration, and the stage of development when it occurs. Mild exposures during the preimplantation period and more severe exposures during embryonic and fetal development often result in prenatal death and abortion. Hyperthermia also causes a wide range of structural and functional defects. The central nervous system (CNS) is most at risk probably because it cannot compensate for the loss of prospective neurons by additional divisions by the surviving neuroblasts and it remains at risk at stages throughout pre- and postnatal life. In experimental animals the most common defects are of the neural tube, microphthalmia, cataract, and micrencephaly, with associated functional and behavioral problems. Defects of craniofacial development including clefts, the axial and appendicular skeleton, the body wall, teeth, and heart are also commonly found. Nearly all these defects have been found in human epidemiological studies following maternal fever or hyperthermia during pregnancy. Suggested future human studies include problems of CNS function after exposure to influenza and fever, including mental retardation, schizophrenia, autism, and cerebral palsy. 相似文献
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《Evolutionary Applications》2018,11(5):762-767
We argue that reproductive suppression has clinical implications beyond its contribution to the burden of spontaneous abortion. We theorize that the incidence of births before the 28th week of gestation, which contribute disproportionately to infant morbidity and mortality, varies over time in part due to reproductive suppression in the form of selection in utero. We further theorize that the prevalence of structural birth defects among survivors to birth from conception cohorts gauges selection in utero. We based these theories on literature positing that natural selection conserved mechanisms that spontaneously abort “risky” pregnancies including those otherwise likely to yield infants with structural birth defects or small‐for‐gestational age males. We test our theory using high‐quality birth defect surveillance data. We identify 479,885 male infants exposed to strong selection defined as membership in conception cohorts ranked in the lowest quartile of odds of a birth defect among live‐born females. We estimate the risk of periviable birth among these infants as a function of selective pressure as well as of mother's race/ethnicity and age. We find that male infants from exposed conception cohorts exhibited 10% lower odds of periviable birth than males from other conception cohorts. Our findings support the argument that selection in utero has implications beyond its contribution to the burden of spontaneous abortion. 相似文献
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Suzanne M. Gilboa Kyung A. Lee Mary E. Cogswell Flavia K. Traven Lorenzo D. Botto Tiffany Riehle‐Colarusso Adolfo Correa Coleen A. Boyle the National Birth Defects Prevention Study 《Birth defects research. Part A, Clinical and molecular teratology》2014,100(9):647-657
BACKGROUND In a recent study, high maternal periconceptional intake of vitamin E was found to be associated with risk of congenital heart defects (CHDs). To explore this association further, we investigated the association between total daily vitamin E intake and selected birth defects. METHODS: We analyzed data from 4525 controls and 8665 cases from the 1997 to 2005 National Birth Defects Prevention Study. We categorized estimated periconceptional energy‐adjusted total daily vitamin E intake from diet and supplements into quartiles (referent, lowest quartile). Associations between quartiles of energy‐adjusted vitamin E intake and selected birth defects were adjusted for demographic, lifestyle, and nutritional factors. RESULTS: We observed a statistically significant association with the third quartile of vitamin E intake (odds ratio [OR], 1.17; 95% confidence interval [CI], 1.01–1.35) and all CHDs combined. Among CHD sub‐types, we observed associations with left ventricular outflow tract obstruction defects, and its sub‐type, coarctation of the aorta and the third quartile of vitamin E intake. Among defects other than CHDs, we observed associations between anorectal atresia and the third quartile of vitamin E intake (OR, 1.66; 95% CI, 1.01–2.72) and hypospadias and the fourth quartile of vitamin E intake (OR, 1.42; 95% CI, 1.09–1.87). CONCLUSION: Selected quartiles of energy‐adjusted estimated total daily vitamin E intake were associated with selected birth defects. However, because these few associations did not exhibit exposure‐response patterns consistent with increasing risk associated with increasing intake of vitamin E, further studies are warranted to corroborate our findings. Birth Defects Research (Part A), 100:647–657, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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Jennifer A. Makelarski Paul A. Romitti Lixian Sun Trudy L. Burns Charlotte M. Druschel Lucina Suarez Andrew F. Olshan Anna Maria Siega‐Riz Richard S. Olney and the National Birth Defects Prevention Study 《Birth defects research. Part A, Clinical and molecular teratology》2013,97(3):152-160
BACKGROUND: Neural tube defects (NTD)s, which occur when the neural tube fails to close during early gestation, are some of the most common birth defects worldwide. Alcohol is a known teratogen and has been shown to induce NTDs in animal studies, although most human studies have failed to corroborate these results. Using data from the National Birth Defects Prevention Study, associations between maternal reports of periconceptional (1 month prior through 2 months postconception) alcohol consumption and NTDs were examined. METHODS: NTD cases and unaffected live born control infants, delivered from 1997 through 2005, were included. Interview reports of alcohol consumption (quantity, frequency, variability, and type) were obtained from 1223 case mothers and 6807 control mothers. Adjusted odds ratios (aOR)s and 95% confidence intervals were estimated using multivariable logistic regression analysis. RESULTS: For all NTDs combined, most aORs for any alcohol consumption, one or more binge episodes, and different type(s) of alcohol consumed were near unity or modestly reduced (≥0.7<aOR≤1.1) and were not statistically significant. Findings were similar for individual NTD subtypes. CONCLUSIONS: These findings suggest no elevated association between maternal periconceptional alcohol consumption and NTDs. Underreporting of alcohol consumption, due to negative social stigma associated with alcohol consumption during pregnancy, and limited reports for mothers with early pregnancy loss of a fetus with an NTD may have affected the estimated odds ratios. Future studies should aim to increase sample sizes for less prevalent subtypes, reduce exposure misclassification, and improve ascertainment offetal deaths and elective terminations. Birth Defects Research (Part A), 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Meijer WM de Jong-Van den Berg LT van den Berg MD Verheij JB de Walle HE 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(4):249-252
BACKGROUND: Clomiphene, a drug used to induce ovulation, is chemically related to diethylstilbestrol (DES). DES is associated with vaginal cancer and infertility among daughters and with hypospadias among second-generation male offspring. Because clomiphene has a long half-life and metabolites have been found in feces up to 6 weeks after administration, fetal exposure is possible if the mother took this drug prior to becoming pregnant. METHODS: Case-control analyses were performed to investigate the association between clomiphene exposure and hypospadias. Cases were all male subjects registered in the European Concerted Action on Congenital Anomalies and Twins (EUROCAT) Northern Netherlands registry for congenital anomalies with nonsyndromal hypospadias. Controls were all male children born without hypospadias, including those with chromosomal and monogenic defects. Logistic regression analyses were performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of 392 cases, 7 (1.8%) were exposed to clomiphene compared with 64 of 4538 controls (1.4%). For penoscrotal hypospadias, we found that the OR was significantly increased (6.08; 95% CI, 1.40-26.33); for the mild and moderate forms of hypospadias, the ORs were not increased. CONCLUSIONS: Because penoscrotal hypospadias is rare, the effect is diluted when all forms of hypospadias are studied as a group. Therefore, our study stresses the importance of studying birth defects on as detailed a level as possible. Other studies should be conducted to confirm our findings. 相似文献
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Carissa M. Rocheleau Stephen J. Bertke Christina C. Lawson Paul A. Romitti Wayne T. Sanderson Sadia Malik Philip J. Lupo Tania A. Desrosiers Erin Bell Charlotte Druschel Adolfo Correa Jennita Reefhuis the National Birth Defects Prevention Study. 《Birth defects research. Part A, Clinical and molecular teratology》2015,103(10):823-833
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Marie I. Blomberg Bengt Källén 《Birth defects research. Part A, Clinical and molecular teratology》2010,88(1):35-40
BACKGROUND : The objective of this study was to assess, in a large data set from Swedish Medical Health Registries, whether maternal obesity and maternal morbid obesity were associated with an increased risk for various structural birth defects. METHODS : The study population consisted of 1,049,582 infants born in Sweden from January 1, 1995, through December 31, 2007, with known maternal weight and height data. Women were grouped in six categories of body mass index (BMI) according to World Health Organization classification. Infants with congenital birth defects were identified from three sources: the Swedish Medical Birth Registry, the Register of Birth Defects, and the National Patient Register. Maternal age, parity, smoking, and year of birth were thought to be potential confounders and were included as covariates in the adjusted odds ratio analyses. RESULTS : Ten percent of the study population was obese. Morbid obesity (BMI ≥ 40) occurred in 0.7%. The prevalence of congenital malformations was 4.7%, and the prevalence of relatively severe malformations was 3.2%. Maternal prepregnancy morbid obesity was associated with neural tube defects OR 4.08 (95% CI 1.87–7.75), cardiac defects OR 1.49 (95% CI 1.24–1.80), and orofacial clefts OR 1.90 (95% CI 1.27–2.86). Maternal obesity (BMI ≥ 30) significantly increased the risk of hydrocephaly, anal atresia, hypospadias, cystic kidney, pes equinovarus, omphalocele, and diaphragmatic hernia. CONCLUSION : The risk for a morbidly obese pregnant woman to have an infant with a congenital birth defect is small, but for society the association is important in the light of the ongoing obesity epidemic. Birth Defects Research (Part A), 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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This review examines the basal chordate, amphioxus, as a simple model for providing insights into the development and evolution of the vertebrates, with which it shares many features, including a pharynx perforated with gill slits, a dorsal nerve cord, segmented muscles, and a notochord. Conversely, amphioxus is simpler than vertebrates in lacking neural crest and paired cephalic sensory organs. Amphioxus embryos are less derived than those of vertebrates, because it lacks large quantities of yolk and/or extra-embryonic tissues. Embryogenesis involves only a simple folding of tissue layers. In addition, the amphioxus genome lacks the large-scale gene duplications of vertebrates. However, in spite of the comparative simplicity of amphioxus, its developmental mechanisms are proving to be highly conserved with those of vertebrates. Thus, studies of amphioxus development can shed light on similar, but more complex, development of vertebrates. Such studies are especially interesting for their insights into the genetic basis of craniofacial birth defects in humans. 相似文献
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Sarah A. Collier Marilyn L. Browne Sonja A. Rasmussen Margaret A. Honein 《Birth defects research. Part A, Clinical and molecular teratology》2009,85(10):842-849
BACKGROUND: Moderate caffeine intake during pregnancy is common, but little is known about its potential association with birth defects. METHODS: The National Birth Defects Prevention Study is a population‐based, case‐control study of major birth defects, excluding infants with single‐gene disorders and chromosomal abnormalities. This analysis includes infants with cleft lip with or without cleft palate (CL/P) and cleft palate only (CPO), excluding infants whose cleft was secondary to holoprosencephaly or amniotic band sequence. Mothers reported dietary caffeine intake from coffee, tea, sodas, and chocolate in the year before pregnancy and reported intake of medications containing caffeine during pregnancy. We assessed the association between dietary caffeine intake, frequency of consuming each type of caffeinated beverage, medications containing caffeine, and CL/P or CPO among infants born from October 1997 through December 2004. RESULTS: This analysis included 1531 infants with CL/P, 813 infants with CPO, and 5711 infants with no major birth defects (controls). Examining dietary sources among control mothers, 11% reported consuming at least 300 mg of caffeine per day and 17% reported consuming less than 10 mg of caffeine per day; high consumption (≥3 servings per day) was reported by 8% (coffee), 4% (tea), and 15% (sodas); medications containing at least 100 mg caffeine/dose were reported by less than 1%. Although some effect estimates were elevated for moderate caffeine intake from all beverages, estimates were closer to the null for high caffeine levels. Isolated CL/P was associated with use of medications containing at least 100 mg of caffeine per dose. CONCLUSIONS: Our data do not suggest an association between maternal dietary caffeine intake and orofacial clefts, but caffeine‐containing medications merit further study. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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Zhu M Druschel C Lin S 《Birth defects research. Part A, Clinical and molecular teratology》2006,76(6):467-473
BACKGROUND: Little is known about the association between maternal nativity and congenital malformations among Hispanics living in the United States. METHODS: We conducted a cross-sectional study to investigate the association between maternal nativity and various congenital malformations among singleton live-births born to Hispanic women in New York from 1993 to 2001. Birth certificates, used to identify maternal birthplace, were linked with congenital malformation registry files to obtain birth defects outcome. We examined how the risk of birth defects varied by maternal birthplace by estimating the adjusted odds ratios (aORs) using logistic regression. RESULTS: A foreign maternal birth showed statistically negative associations with overall congenital malformations (aOR, 0.70; 95% CI, 0.68-0.73), cardiovascular defects (aOR, 0.85; 95% CI, 0.77-0.93), central nervous system defects (aOR, 0.76; 95% CI, 0.63-0.91), and multiple defects (aOR, 0.80; 95% CI, 0.74-0.86). Specifically, foreign-born Hispanic women were statistically at reduced risk to deliver live babies with cleft palate (aOR, 0.56; 95% CI, 0.40-0.80), atresia and stenosis of rectum or anus (aOR, 0.58; 95% CI, 0.35-0.97), and craniosynostosis (aOR, 0.71; 95% CI, 0.51-0.99). Hispanic mothers born in Puerto Rico had a similar risk of delivering children with birth defects compared to U.S.-born Hispanic mothers. In contrast, Hispanic mothers born in Mexico, or Cuba and Central and South America were at reduced risk of delivering infants with overall congenital malformations (aOR, 0.64; 95% CI, 0.60-0.67) and (aOR, 0.65; 95% CI, 0.63-0.68), respectively. CONCLUSIONS: Foreign-born Hispanic mothers had a slightly lower risk to deliver live-born singleton infants with major congenital malformations than did U.S. born Hispanic mothers. 相似文献
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